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what is the inch of fish per gallon of water rule ?????

what the name suggest. the rule is (but i don't follow it) is that there is one ich of fish per gallon of water. goldfish is that 1 ich of fish is = to 5 gallons of water.

howeve you can not put a 29" fish in a 29 gallon. jus thought i'd mention that

It's a rather obsolete rule that says the total amount of fish you can have is based on the adult length of the fish... if you have a twenty gallon tank, supposedly you can have 20 inches of adult fish.

Many people have forsaken this rule for the surface area rule. The surface area takes into account gas exchange. For this rule, you take length x width of the tank and divide by 12.

I'm sure there's other rules as well, but I generally use the surface area rule. *shrugs*

~Meow. Thus spoke the cat.~

Inch per gallon only works in a few cases. A better guideline to follow is to use the surface area of the tank. Oxygenation occurs on the surface of the tank, as well as was already hinted at...just because a tank has a certian ammount of gallons doesn't mean it has the same ammount of space. For instance a 29 gallon is a tall tank whereas a 30 gallon is a long tank.

Surface area/12 = approximate ammount of inches of fish.

This doesn't work for fish like angels that need tall tanks, goldfish that need ponds, or plecos that produce more waste than some other fish. Remember it's a guideline, always investigate your future purchases prior to visiting the LFS.

^_^

[hr width='40%']"I'm alright, I'm alright
It only hurts when I breathe"

Every stocking rule has its pitfalls. Personally, I think the inch per gallon rule is the most flawed. I don't even see how it makes sense to begin with. Fish are three dimensional, not flat measures of length. There are a number of factors to consider when thinking about stocking: the fish's adult size, and just as important, behavior (activity level, agression level, schooling behavior, feeding habits, bio-load impact, structure requirements i.e. needing caves, rocks or plants, etc. - the list could go on).

Are you wondering about a particular stocking scheme you have in mind? If so, please tell us and we'll give you our best advice and share our experiences. But please don't base your plans on a shoddy rule like "inches per gallon"

Then again, if you just want to know for the heck of it, then there ya go - one inch per gallon.

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Back in the saddle!

It's a good starting rule that can help beginners keep from way overstocking their tanks with lots of small fish. It's too simple and basic though to work with many situations. You need to take into account alot of other things as well.